A survey of real-time soft-shadow algorithms

Jean-Marc Hasenfratz 1, 2 Marc Lapierre 1, 3 Nicolas Holzschuch 1 François X. Sillion 1
1 ARTIS - Acquisition, representation and transformations for image synthesis
GRAVIR - IMAG - Graphisme, Vision et Robotique, Inria Grenoble - Rhône-Alpes, CNRS - Centre National de la Recherche Scientifique : FR71
3 MOVI - Modeling, localization, recognition and interpretation in computer vision
GRAVIR - IMAG - Graphisme, Vision et Robotique, Inria Grenoble - Rhône-Alpes, CNRS - Centre National de la Recherche Scientifique : FR71
Abstract : Recent advances in GPU technology have produced a shift in focus for real-time rendering applications, whereby improvements in image quality are sought in addition to raw polygon display performance. Rendering effects such as antialiasing, motion blur and shadow casting are becoming commonplace and will likely be considered indispensable in the near future. The last complete and famous survey on shadow algorithms -Woo, 1990- has to be updated in particular in view of recent improvements in graphics hardware, which make new algorithms possible. This STAR covers all current methods for real-time shadow rendering, without venturing into slower, high quality techniques based on ray casting or radiosity. Shadows are useful for a variety of reasons: first, they help understand relative object placement in a 3D scene by providing visual cues. Second, they dramatically improve image realism and allow the creation of complex lighting ambiances. Depending on the application, the emphasis is placed on a guaranteed framerate, or on the visual quality of the shadows including penumbra effects or ``soft shadows''. Obviously no single method can render physically correct soft shadows in real-time for any dynamic scene! However our survey aims at providing an exhaustive study allowing a programmer to choose the best compromise for his/her needs. In particular we discuss the advantages, limitations, rendering quality and cost of each algorithm. Recommendations are included based on simple characteristics of the application such as static/moving lights, single or multiple light sources, static/dynamic geometry, geometric complexity, directed or omnidirectional lights, etc. Finally we indicate which methods can efficiently exploit the most recent graphics hardware facilities.
Document type :
Conference papers
Complete list of metadatas

Cited literature [51 references]  Display  Hide  Download


https://hal.inria.fr/inria-00441603
Contributor : Nicolas Holzschuch <>
Submitted on : Wednesday, December 16, 2009 - 10:57:10 PM
Last modification on : Thursday, January 11, 2018 - 6:20:04 AM
Long-term archiving on : Thursday, June 17, 2010 - 11:46:18 PM

Files

RTSoftShadows.pdf
Files produced by the author(s)

Identifiers

  • HAL Id : inria-00441603, version 1

Collections

IMAG | INRIA | UGA

Citation

Jean-Marc Hasenfratz, Marc Lapierre, Nicolas Holzschuch, François X. Sillion. A survey of real-time soft-shadow algorithms. Eurographics State-of-the-art reports, Sep 2003, Granada, Spain. ⟨inria-00441603⟩

Share

Metrics

Record views

522

Files downloads

483